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Manufacturing And Analysis Of A Liga Heat Exchanger For The Surface Of A Tube: A Cooling Simulation Of The Leading Edge Region Of A Turbine Blade, Christophe Marques Jan 2003

Manufacturing And Analysis Of A Liga Heat Exchanger For The Surface Of A Tube: A Cooling Simulation Of The Leading Edge Region Of A Turbine Blade, Christophe Marques

LSU Doctoral Dissertations

Fabricating nickel micro heat exchangers directly on planar or non-planar metal surfaces has been demonstrated using the LIGA micromachining process. These heat exchangers can effectively control the temperature of surfaces in high heat flux applications. Of particular interest is the temperature control of gas turbine engine components. The locations in the gas turbine engine where improved, efficient cooling is required includes gas turbine blades, stator vanes, the turbine disk, and the combustor liner. In this dissertation, the primary application of interest is the use of such heat exchangers to cool airfoils such as turbine blades. In the first part of …

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The Ecology Of Two Estuarine-Dependent Tonguefishes, The Blackcheek Tonguefish (Symphurus Plagiusa) And The Offshore Tonguefish (S. Civitatium), In Coastal Louisiana, Theodore Scott Switzer Jan 2003

The Ecology Of Two Estuarine-Dependent Tonguefishes, The Blackcheek Tonguefish (Symphurus Plagiusa) And The Offshore Tonguefish (S. Civitatium), In Coastal Louisiana, Theodore Scott Switzer

LSU Doctoral Dissertations

The pattern and process of wetland loss in coastal Louisiana has the potential to influence the distribution and abundance of fishes and macroinvertebrates that utilize inshore estuarine habitat as nurseries during their early life histories. Current management plans designed to stabilize marsh elevations, such as freshwater diversions, may also influence the distribution and abundance of estuarine-dependent nekton. Given the importance of nursery function of inshore estuaries in coastal Louisiana, it is of interest to explore the response of estuarine-dependent organisms to environmental gradients. To this end I examined the ecology of two sympatric tonguefishes, the blackcheek tonguefish (Symphurus plagiusa) and …

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On The Geometry And Topology Of Moduli Spaces Of Multi-Polygonal Linkages, Michael Edward Holcomb Jan 2003

On The Geometry And Topology Of Moduli Spaces Of Multi-Polygonal Linkages, Michael Edward Holcomb

LSU Doctoral Dissertations

The geometric, topological, and symplectic properties of moduli spaces (spaces of configurations modulo rotations and translations) of polygonal linkages have been studied by Kapovich, Millson, and Kamiyama, et. al. One can form a polygonal linkage by taking two free linkages and identifying initial and terminal vertices. This can be generalized so that one takes three free linkages and identifies initial and terminal vertices. Then one obtains a linkage which contains multiple polygons, any two of which have shared edges. The geometric and topological properties of moduli spaces of these multi-polygonal linkages are studied. These spaces turn out to be compact …

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The Relationship Between Elementary School Foreign Language Study In Grades Three Through Five And Academic Achievement On The Iowa Tests Of Basic Skills (Itbs) And The Fourth-Grade Louisiana Educational Assessment Program For The 21st Century (Leap 21) Test, Carolyn Joyce Taylor-Ward Jan 2003

The Relationship Between Elementary School Foreign Language Study In Grades Three Through Five And Academic Achievement On The Iowa Tests Of Basic Skills (Itbs) And The Fourth-Grade Louisiana Educational Assessment Program For The 21st Century (Leap 21) Test, Carolyn Joyce Taylor-Ward

LSU Doctoral Dissertations

The passage of the federal educational legislation, No Child Left Behind Act of 2001, established foreign languages as a core curricular content area. Nonetheless, educational policy makers at the state and local levels often opt to allocate greater resources and give instructional priority to content areas in which students, and ultimately the school systems themselves, are held accountable through high-stakes testing. Although foreign languages are designated as a core content area, instructional emphasis continues to be placed on curricular areas that factor into state educational accountability programs. The present study employed a mixed-methodology design. The primary goal was to explore …

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Off Road Vehicle Soil Suitability Analysis Within The Kisatchie National Forest, Jacqueline Avellanoza Prudente Jan 2003

Off Road Vehicle Soil Suitability Analysis Within The Kisatchie National Forest, Jacqueline Avellanoza Prudente

LSU Doctoral Dissertations

Soil degradation due to improper use of off road vehicle (ORV) is among the major problems in the Kisatchie National Forest (KNF), especially in Catahoula (CRD), Evangeline Unit, Calcasieu (ERD), and Kisatchie Ranger (KRD) districts. The USDA-Forest Service (USFS) maintains designated trails within the forest, but many ORV users create their own trails. To address this issue, a research project was initiated in 2001 to assess the suitability of KNF soils for ORV traffic using Geographical Information System (GIS) software. The objectives were achieved by utilizing soil properties, rainfall events, soil trafficability ratings, Keetch-Byram Drought Index (KBDI), and infiltration parameters. …

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The Perceptions Of Effects Of A Study Skills Course, "Dynamics Of Effective Study," On The Academic Achievement Of African American Students At A Dedicated Academic Magnet High School, Josephine Ann Allen Jan 2003

The Perceptions Of Effects Of A Study Skills Course, "Dynamics Of Effective Study," On The Academic Achievement Of African American Students At A Dedicated Academic Magnet High School, Josephine Ann Allen

LSU Doctoral Dissertations

The purpose of this study was to examine the perceptions of students, teachers, and administrators on the effectiveness of a study skills course, "Dynamics of Effective Study," on the academic achievement of African American students at a dedicated academic magnet high school. Qualitative research methods were utilized in this study. Fifteen African American students who completed the study skills course, fifteen African American students who did not take or complete the study skills course, five former study skills teachers, and three administrators from the dedicated academic magnet high school volunteered to participate in the study. Open-ended interviews were conducted with …

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Large Eddy Simulations Of Complex Turbulent Flows, Mayank Tyagi Jan 2003

Large Eddy Simulations Of Complex Turbulent Flows, Mayank Tyagi

LSU Doctoral Dissertations

In this dissertation a solution methodology for complex turbulent flows of industrial interests is developed using a combination of Large Eddy Simulation (LES) and Immersed Boundary Method (IBM) concepts. LES is an intermediate approach to turbulence simulation in which the onus of modeling of “universal” small scales is appropriately transferred to the resolution of “problem-dependent” large scales or eddies. IBM combines the efficiency inherent in using a fixed Cartesian grid to compute the fluid motion, along with the ease of tracking the immersed boundary at a set of moving Lagrangian points. Numerical code developed for this dissertation solves unsteady, filtered …

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Constraint Preserving Boundary Conditions For The Linearized Einstein Equations, Gioel Calabrese Jan 2003

Constraint Preserving Boundary Conditions For The Linearized Einstein Equations, Gioel Calabrese

LSU Doctoral Dissertations

The successful construction of long time convergent finite difference schemes approximating highly gravitating systems in general relativity remains an elusive task. The presence of constraints and the introduction of artificial time-like boundaries contribute significantly to the difficulty of this problem. Whereas in the absence of boundaries the Bianchi identities ensure that the constraints vanish during evolution provided that they are satisfied initially, this is no longer true when time-like boundaries are introduced. In this work we consider the linearization around the Minkowski space-time in Cartesian coordinates of the generalized Einstein-Christoffel system and analyze different kinds of boundary conditions that are …

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Genome Analysis: Mutation Analysis Using Near Infrared Laser-Induced Fluorescence (Nir-Lif) And Single Molecule Detection In Microfluidic Devices, Musundi Ben Wabuyele Jan 2003

Genome Analysis: Mutation Analysis Using Near Infrared Laser-Induced Fluorescence (Nir-Lif) And Single Molecule Detection In Microfluidic Devices, Musundi Ben Wabuyele

LSU Doctoral Dissertations

A number of genotyping methods have been developed for mutation analysis, each of which has its own unique advantage. DNA amplification via polymerase chain reaction (PCR) provides an unlimited supply of material for subsequent genetic analysis even in case where only a single copy of the DNA molecule is present in the sample. Research presented in this dissertation first examines the efficiency of in vitro amplification of single copy DNA with subsequent sequencing analysis of PCR product. The PCR products (amplicons) were investigated for possible alteration, distortions or mutations due to the amplification process. The sequencing data for single copy …

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Group Theoretical Approach To Pairing And Non-Linear Phenomena In Atomic Nuclei, Kristina D. Launey Jan 2003

Group Theoretical Approach To Pairing And Non-Linear Phenomena In Atomic Nuclei, Kristina D. Launey

LSU Doctoral Dissertations

The symplectic sp(4) algebra provides a natural framework for studying proton-neutron (pn) and like-nucleon pairing correlations as well as higher-J pn interactions in nuclei when protons and neutrons occupy the same shell. While these correlations manifest themselves most clearly in the binding energies of 0+ ground states, they also have a large effect on the spectra of excited isobaric analog 0+ states. With a view towards nuclear structure applications, a fermion realization of sp(4) is explored and its q-deformed extension, sp(4)q, is constructed for single and multiple shells. The su(2)(q) substructures that enter are associated with isospin symmetry and with …

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Influences Of Selected Demographic Variables On The Career Decision-Making Self-Efficacy Of College Seniors, Mary Edith Whitehead Stacy Jan 2003

Influences Of Selected Demographic Variables On The Career Decision-Making Self-Efficacy Of College Seniors, Mary Edith Whitehead Stacy

LSU Doctoral Dissertations

The study was designed (1) to describe college seniors demographically, (2) to assess college seniors perceived level of career-decision making self-efficacy (CDMSE), (3) to examine the relationship between the participant’s CDMSE scores, as measured by the subscales of the Career Decision Self-Efficacy Scale – Short Form© (CDSE-SF), and selected demographic characteristics, and; (4) to determine if a model existed to explain a significant portion of variance in CDMSE based on the selected demographic characteristics. The sample consisted of 382 college seniors attending a four-year public university completing the application for graduation process in the 2002 fall semester. Along with the …

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Finite-Horizon Operations Planning For A Lean Supply Chain System, Ahmad Diponegoro Jan 2003

Finite-Horizon Operations Planning For A Lean Supply Chain System, Ahmad Diponegoro

LSU Doctoral Dissertations

This dissertation studies an operational policy for a lean supply chain system consisting of a manufacturer, multiple suppliers and multiple buyers. The manufacturer procures raw materials from the suppliers and converts them into finished products, which are then shipped in batches to the buyers at certain intervals of times. Three distinct but inseparable problems are addressed: single supplier and single buyer with fixed delivery size (FD), multiple suppliers and multiple buyers with individual delivery schedule (MD), and time dependent delivery quantity with trend demand (TD). The mathematical formulations of these supply systems are categorized as mixed-integer, nonlinear programming problems (MINLAP) …

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Improved Bottomhole Pressure Control For Underbalanced Drilling Operations, Carlos Perez-Tellez Jan 2003

Improved Bottomhole Pressure Control For Underbalanced Drilling Operations, Carlos Perez-Tellez

LSU Doctoral Dissertations

Maintaining underbalanced conditions from the beginning to the end of the drilling process is necessary to guarantee the success of jointed-pipe underbalanced drilling (UBD) operations by avoiding formation damage and potential hazardous drilling problems such as lost circulation and differential sticking. However, maintaining these conditions is an unmet challenge that continues motivating not only research but also technological developments. This research proposes an UBD flow control procedure, which represents an economical method for maintaining continuous underbalanced conditions and, therefore, to increase well productivity by preventing formation damage. It is applicable to wells that can flow without artificial lift and within …

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Hydrodynamic And Sediment Transport Modeling Of Deltaic Sediment Processes, Hassan Shahid Mashriqui Jan 2003

Hydrodynamic And Sediment Transport Modeling Of Deltaic Sediment Processes, Hassan Shahid Mashriqui

LSU Doctoral Dissertations

This dissertation tests the hypothesis that the early phases of deltaic bar and distributary channel formation and sediment transport on an adverse slope could be simulated with a 2D finite element sediment transport model. The models used were RMA2 and SED2D modules of the TABS-MD model suite. A finite element mesh of the lower Atchafalaya River and the delta was developed, using the Surface Water Modeling System (SMS) software package. Calibration and validation of the model were performed, using data collected during field surveys and from available Atchafalaya River archived flow, suspended sediment, and dredging records. In a test simulation …

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The C-Function For Non-Compactly Causal Symmetric Spaces, Bernhard Krötz, Gestur Ólafsson Dec 2002

The C-Function For Non-Compactly Causal Symmetric Spaces, Bernhard Krötz, Gestur Ólafsson

Faculty Publications

No abstract provided.

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Embedding Dissipation And Decoherence In Unitary Evolution Schemes, A. R.P. Rau, R. A. Wendell Nov 2002

Embedding Dissipation And Decoherence In Unitary Evolution Schemes, A. R.P. Rau, R. A. Wendell

Faculty Publications

The dissipation and decoherence in unitary evolution schemes of quantum physics was discussed. The master equations of damped, driven two-level system were used in the density matrix. The elements of density matrix were embedded in higher-dimensional Liouville-Bloch equations. The density matrix was solved as a function of time using nonunitary integration.

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A Quantum Rosetta Stone For Interferometry, Hwang Lee, Pieter Kok, Jonathan P. Dowling Nov 2002

A Quantum Rosetta Stone For Interferometry, Hwang Lee, Pieter Kok, Jonathan P. Dowling

Faculty Publications

Heisenberg-limited measurement protocols can be used to gain an increase in measurement precision over classical protocols. Such measurements can be implemented using, for example, optical Mach-Zehnder interferometers and Ramsey spectroscopes. We address the formal equivalence between the Mach-Zehnder interferometer, the Ramsey spectroscope and a generic quantum logic circuit. Based on this equivalence we introduce the 'quantum Rosetta stone', and we describe a projective-measurement scheme for generating the desired correlations between the interferometric input states in order to achieve Heisenberg-limited sensitivity. The Rosetta stone then tells us that the same method should work in atom spectroscopy.

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Faculty Senate Resolution 03-04, Louisiana State University And Agricultural & Mechanical College Nov 2002

Faculty Senate Resolution 03-04, Louisiana State University And Agricultural & Mechanical College

LSU Faculty Senate Publications

Faculty Senate Resolution on grades and standards, adopted on November 7, 2002.

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Nitrogen Loading Into An Urban Estuary: Lake Pontchartrain (Louisiana, U.S.A.), R. Eugene Turner, Q. Dortch, Dubravko Justic, Erick M. Swenson Nov 2002

Nitrogen Loading Into An Urban Estuary: Lake Pontchartrain (Louisiana, U.S.A.), R. Eugene Turner, Q. Dortch, Dubravko Justic, Erick M. Swenson

Faculty Publications

We constructed a nitrogen loading budget for the Lake Pontchartrain watershed located north of New Orleans, Louisiana (U.S.A.). Water quality measurements, discharge estimates, and literature values were used to establish the annual and seasonal variations in loading rates for total nitrogen and nitrate. The relatively stable annual loadings (million kg N) are about 10× that of the pre-settlement nitrogen loading, and come from atmosphere (1.3), the watershed (7.8), pumped urban runoff from New Orleans (1.0), and leakage through the Bonnet Carré flood control structure (0.5–0.9). Relatively minor additional amounts come from nitrogen fixation in the Lake. Occasional openings of the …

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The Cauchy Problem And Stability Of Solitary-Wave Solutions For Rlw-Kp-Type Equations, Jerry L. Bona, Yue Liu, Michael M. Tom Nov 2002

The Cauchy Problem And Stability Of Solitary-Wave Solutions For Rlw-Kp-Type Equations, Jerry L. Bona, Yue Liu, Michael M. Tom

Faculty Publications

The Kadomtsev-Petviashvilli (KP) equation, (ut + ux + uux + uxxx )x + euyy = 0, (*) arises in various contexts where nonlinear dispersive waves propagate principally along the x-axis, but with weak dispersive effects being felt in the direction parallel to the y-axis perpendicular to the main direction of propagation. We propose and analyze here a class of evolution equations of the form (ut + ux, + upux + Lut)x + euyy = 0, (* *) which provides an alternative to Eq. (*) in the same way the regularized long-wave equation is related to the classical Korteweg-de …

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Modification Of An Injection Molding Machine To Mold Micro Parts With A Liga Mold, Emil John Geiger Oct 2002

Modification Of An Injection Molding Machine To Mold Micro Parts With A Liga Mold, Emil John Geiger

Honors Capstones

No abstract provided.

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Faculty Senate Resolution 03-01, Louisiana State University And Agricultural & Mechanical College Oct 2002

Faculty Senate Resolution 03-01, Louisiana State University And Agricultural & Mechanical College

LSU Faculty Senate Publications

Faculty Senate Resolution on increasing admissions standards, adopted on October 2, 2002.

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Triples Of Arrangements And Local Systems, Daniel C. Cohen Oct 2002

Triples Of Arrangements And Local Systems, Daniel C. Cohen

Faculty Publications

For a triple of complex hyperplane arrangements, there is a well-known long exact sequence relating the cohomology of the complements. We observe that this result extends to certain local coefficient systems, and use this extension to study the characteristic varieties of arrangements. We show that the first characteristic variety may contain components that are translated by characters of any order, thereby answering a question of A. Suciu.

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The Nature Of Interchain Excitations In Conjugated Polymers: Spatially-Varying Interfacial Solvatochromism Of Annealed Meh-Ppv Films Studied By Near-Field Scanning Optical Microscopy (Nsom), Richard D. Schaller, Lynn F. Lee, Justin C. Johnson, Louis H. Haber, Richard J. Saykally, John Vieceli, Ilan Benjamin, Thuc Quyen Nguyen, Benjamin J. Schwartz Sep 2002

The Nature Of Interchain Excitations In Conjugated Polymers: Spatially-Varying Interfacial Solvatochromism Of Annealed Meh-Ppv Films Studied By Near-Field Scanning Optical Microscopy (Nsom), Richard D. Schaller, Lynn F. Lee, Justin C. Johnson, Louis H. Haber, Richard J. Saykally, John Vieceli, Ilan Benjamin, Thuc Quyen Nguyen, Benjamin J. Schwartz

Faculty Publications

The nature of interchain excitations in conjugated polymers was discussed. The spatially-varying solvatochromism of annealed poly(2-methoxy-5-(2′-ethylhexyloxy)-1,4-phenylene vinylene) (MEH-PPV) films were studied by near-field scanning optical microscopy (NSOM). The solvatochromic spectral shifts of the interfacial luminescence were measured as a function of solvent polarity. The results were analyzed with an interfacial dielectric continuum model to determine the dipole moment of emissive excited states.

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Local Systems On Nilpotent Orbits And Weighted Dynkin Diagrams, Pramod N. Achar, Eric N. Sommers Sep 2002

Local Systems On Nilpotent Orbits And Weighted Dynkin Diagrams, Pramod N. Achar, Eric N. Sommers

Faculty Publications

We study the Lusztig-Vogan bijection for the case of a local system. We compute the bijection explicitly in type A for a local system and then show that the dominant weights obtained for different local systems on the same orbit are related in a manner made precise in the paper. We also give a conjecture (putatively valid for all groups) detailing how the weighted Dynkin diagram for a nilpotent orbit in the dual Lie algebra should arise under the bijection. © 2002 American Mathematical Society.

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Non-Semisimple Hopf Algebras Of Dimension P2, Siu Hung Ng Sep 2002

Non-Semisimple Hopf Algebras Of Dimension P2, Siu Hung Ng

Faculty Publications

Let H be, finite-dimensional Hopf algebra with antipode S of dimension pq over an algebraically closed field of characteristic 0, where p ≤ q are odd primes. If H is not semisimple, then the order of S4 is p, and Tr(S2p) is an integer divisible by p2. In particular, if dim H = p2, we prove that H is isomorphic to a Taft algebra. This completes the classification for the Hopf algebras of dimension p2. © 2002 Elsevier Science (USA). All rights reserved.

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Analysis And Classification Of Nonlinear Dispersive Evolution Equations In The Potential Representation, U. A. Eichmann, A. Ludu, J. P. Draayer Jul 2002

Analysis And Classification Of Nonlinear Dispersive Evolution Equations In The Potential Representation, U. A. Eichmann, A. Ludu, J. P. Draayer

Faculty Publications

A potential representation for the subset of travelling solutions of nonlinear dispersive evolution equations is introduced. The procedure involves reduction of a third-order partial differential equation to a first-order ordinary differential equation. The potential representation allows us to deduce certain properties of the solutions without the actual need to solve the underlying evolution equation. In particular, the paper deals with the so-called K(n, m) equations. Starting from their respective potential representations it is shown that these equations can be classified according to a simple point transformation. As a result, e.g., all equations with linear dispersion join the same equivalence class …

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Relaxation Through Homogenization For Optimal Design Problems With Gradient Constraints, R. Lipton Jul 2002

Relaxation Through Homogenization For Optimal Design Problems With Gradient Constraints, R. Lipton

Faculty Publications

The problem of the relaxation of optimal design problems for multiphase composite structures in the presence of constraints on the gradient of the state variable is addressed. A relaxed formulation for the problem is given in the presence of either a finite or infinite number of constraints. The relaxed formulation is used to identify minimizing sequences of configurations of phases.

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The Structure Of Haplotype Blocks In The Human Genome, Stacey B. Gabriel, Stephen F. Schaffner, Huy Nguyen, Jamie M. Moore, Jessica Roy, Brendan Blumenstiel, John Higgins, Matthew Defelice, Amy Lochner, Maura Faggart, Shau Neen Liu-Cordero, Charles Rotimi, Adebowale Adeyemo, Richard Cooper, Ryk Ward, Eric S. Lander, Mark J. Daly, David Altshuler Jun 2002

The Structure Of Haplotype Blocks In The Human Genome, Stacey B. Gabriel, Stephen F. Schaffner, Huy Nguyen, Jamie M. Moore, Jessica Roy, Brendan Blumenstiel, John Higgins, Matthew Defelice, Amy Lochner, Maura Faggart, Shau Neen Liu-Cordero, Charles Rotimi, Adebowale Adeyemo, Richard Cooper, Ryk Ward, Eric S. Lander, Mark J. Daly, David Altshuler

Faculty Publications

Haplotype-based methods offer a powerful approach to disease gene mapping, based on the association between causal mutations and the ancestral haplotypes on which they arose. As part of The SNP Consortium Allele Frequency Projects, we characterized haplotype patterns across 51 autosomal regions (spanning 13 megabases of the human genome) in samples from Africa, Europe, and Asia. We show that the human genome can be parsed objectively into haplotype blocks; sizable regions over which there is little evidence for historical recombination and within which only a few common haplotypes are observed. The boundaries of blocks and specific haplotypes they contain are …

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On Interval Clutters, Guoli Ding Jun 2002

On Interval Clutters, Guoli Ding

Faculty Publications

A hypergraph is an interval hypergraph if its vertices can be linearly ordered so that all its edges are consecutive sets. Interval hypergraphs have been characterized by Tucker (J. Combin. Theory 12 (1972) 153) in terms of excluded subhypergraphs. In this paper, we strengthen Tucker's result for clutters by characterizing interval clutters in terms of excluded partial clutters, as well as excluded minors. Since minor and partial clutter relations are much more restrictive than the subhypergraph relation, our results are more applicable than Tucker's result in, many situations. As a lemma, we also determine all the minor minimal clutters that …

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